Highlands Ranch is an unincorporated community located in Douglas County, Colorado, within the United States. It is officially defined by the United States Census Bureau as a census-designated place (CDP) and serves as part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area.
As of the 2020 census, Highlands Ranch had a population of 105,631, making it the largest community in Douglas County and the most populous unincorporated community in the state of Colorado. The community is served by the Highlands Ranch Metropolitan District and encompasses the ZIP codes 80126, 80129, 80130, and 80163.